Well-boring drill bit



Aug. 6, 1929. A. B. CROSS ET AL WELL BORING DRILL BIT Filed June 18.1928 2 Sheets-Sheet.

Aug. 6, 1929. A. B. cRoss ET AL WELL BORING DRILL BIT Filed June 18,192.8

2 Sheets-Sheet.

INVENTOR HdML/U- DMJ /v/ ATTORNEY Patented Aug. 6, 1929.

UNITED STATES PATENT oFFflcl-z.

ANDREW B. CROSS AND WILLIAM H. FRAZIER, OF DENVER, COLORADO..

WELL-BORING DRILL Brr. y

Application filed June 18,

Further, to provide a drill, comprising a.

head which is made up of a plurality of spaced l connected pipesect-ions arranged one within the other, the innermost pipe being ofmuch greater length than the others' and forming a drill stem for thehead, the said stem being connected with the spaces between the pipesections so as to supply water thereto; -rotary cutters being disposedbetween pairs of the pipes at their lower ends, the rollers beingarranged in sets and the rollers of each set being mounted on a common'`shaftf which is adapted to `be secured 1n recesses in the lower endportions of the pipe sectlons.

Further, to provide a drill of this character, in which the cutters canbe arranged either to form a core drill, or to cut away the entire wellbottom as in the usual manner.

These objects are accomplished by the character or' drill illustrated inthe accompanyin" drawings, in which,

Fig. l is a vertical sectional view through a well showing the improveddrill therein in side elevation, and means for operating the same. y

Fig. 2 is anenlarged vertical sectional view through the drill, showingmore clearly the manner in which water vis supplied to the cutters. thedrill being adapted for cutting c ores.

Fig. 3 is a bottom view of Figure 2.

Fig. 4 is a fragmental sectional View, showing-a slightly differentarrangement of. the cutters.

Fig. 5 is a vertical sectional view through a core drill, showing adifferent Ln'fianneroi lconstructing the drill head, and showing corecutterswhich rotate on'a vertical axls.

Fig. 6 is a bottom view of a drill adapted.

. the drive shaftfor the cutter head and will 1928. serial No. 286,198.l

for cutting away the entire bottom surface of the well hole.-

Fig. 7 is a fragmental side View, showiralg the manner Iof mounting oneof the side cutters or reamers. Y .f

Fig. 8 is a sectional View"7 on the 4line 8-8 of Figure 7. I

Fig. 9 is a vertical sectional view, through a portion oi the drillhead, showing one of the side cutters,Cand the manner of mounting 60,the core dutters. A

Fig. l0 is a similar viewfs'howing one of the side cutters mounted so asto swing outward under centrifugal action. y. Fig. ll is a View of thebottom edge' ofone 55 of' the pipesV forming the drill head, showing therecess lin which the squared end of one of the cutter supporting shaftsis mounted. f

Fig.- 12 is a side view of Fig. 11, showing the saddle block which holdsthe end of the cut# 7o ter shaft in place. i Y

Referring to the accompanying drawings, The letter A' designates theimproved drill head, -which is made up of a plurality yof spaced pipesections 1, arranged one within another and secured together in anysuitable manner so las to form a unitary structure. The innermost pipeondrill stem 2 is much longer than the other pipes and constitutes f.hereafter be referred toas the drill stem. In the arrangement shown inall of thepigures excepting Figure 4, the lower edges of the. pipes areall' on the same horizontal plane, and beginning with the outer pipe,they are of progressively increasing length, terminating `with the pipewhich immediately surrounds the cgnter pipe or drill stem. In theconstruction shown in Figures `1 and 2, this progressive increase in thevlength of the pipes forms a stepped arrangement at'their upper ends atan inclination of about forty-five degrees, and a Hat ring 3 rests uponthe edge of each pipe and tightly surrounds the next larger pipe, andthese rings 3 are each welded tothe pipe upon which it rests and to therpipe which it surrounds. In the case of a core drill, thehead is madelong enough to receive a core of the required length, andthi-s length isdeclinedby a lblock 4, which is secured in the drill stem 2 ona'planecorrerbeneath it is cut away, excepting the central sponding tothe top ofthe pipe immediately surrounding the saidl stem, the part ofthe stem2, below the block 4, forming.' the core receiver or barrel/2A.The stem 2 is provided with four equi-distant holes 5, which arepositioned immediately above the block l and the inner ends of pipes 6are welded to the shaft 2,.so as to surround the Aholes 5, and the pipes6 extend out over the top of the head and at a corresponding inclinationthereto. The pipes 6 are either provided with or formed with nipples 7,the ends'of which tit tightly in holes in the flat rings 3, and thisarrangement, water, which is supplied through the shaft 2, passesthrough the holes 5, pipes 6, and nipples 7, to the spaces between thepipe sections 1 and thence to the bottom of the hole bein drilled.

The lower end of the t rill head is provided with two rows'of rotarycutters 8, the axes of which are at right angles and pass through thecenter of the stem`2, and these cutters are arranged in four groups ofthree or more cutters each, three cutters being shown in each group, inFigures 2 and 3, and the cutters may all be of the same diameter, orthey may increase in diameter from theinner to the outer cutter of eachgroup, as shown in Figures 2 and 3. The cuttersare in the form oftoothed wheels or rollers and the cutters of each group are rotatablymounted on a shaft 9, having squared'portions which lit invcorresponding recesses 10 in the ends of the pipe sections, and areheld therein by saddle blocks 12, the end portions of which lit inshallow recesses 13 in the ends of the'pipes on each side of therecesses 10, so as to lie flush with the lower end of the pipe as willbe understood by reference to Fig. 12. These saddles have projectingportions 14, which eX- tend into the recesses 10 and against the squaredportion of the shaft and the end portions of the said projectingportions 14, have a tongue and groove connection with the side walls ofthe grooves 10, as Shown. As shown l in Figures 2 and 3, -the end ofevery other pipe section is cut away or recessed to receive the cutters,and the corresponding cutters in two alined groups of cutters travel" inthe same path, but the cutters in one diametrical line travel indifferent paths from the corresponding cutters in the other diametricalline, whereby the entire surface beneath the head, excepting the core,is cut away, the cutters being thick enough for that purpose.

` The core is formed in the following manner The inner rollers 8A of twoalined groups,

are positioned so that their inner faces travel in a circle whichcoincides with the inner face of the core-receiving barrel 2^ of thedrill stem 2, the core barrel being cut away for that purpose, as shownat 15 in Figures 2 and 3. Thus, as the head rotates, all the surfaceportion or core, which is formed by the cutters SA, and projects intothe core barrel 2^, of the shaft 2 as the head. moves (flownward. Vhen afull length core is completed, it is severed and removed in thefollowing manner z-Diametrically opposite, blocksdt are secured in thelower end of the head, preferably between the second and fourth sectionsfrom the stem and in these blocks are pivotally mounted gravity cuttingdogs 17, which have an up and down swinging movement in the blocks 16,and when in horizontal positions are each long enough t-o extend halfway across the core barrel, the said core harrel being pro'vided withslots 18, through -which the dogs can swing. lVhen the core is forming,the dogsl are swung back to inoperative positions by engagement with thecore, but when the core is completed, upward movement of the drill whilerotating, will cause the' points of thedogs to cut into the core, and asthe drill is slowly lifted, the dogs will continue to cut andatthe sametime will more toward horizontal positions until the core is finallysevered, and rests upon the dogs so that it islifted out of the holewith the drill. As the drill is lifted, while the core is being severed,a space'will be made between the upper end of the core and the block el,and when the drill islifted out of the hole, the core may be removed byirst pushing it up against the block t, when the dogs 17 may be swungback out of the core tube, thus permitting the core to drop out. p

In order that the drill may have sufficient clearance, so as not to bindwhen in operation or when it is being withdrawn from the hole, reamers19 are mounted in the lower end of the drill head, which project beyondthe peripheral surface of the drill and thus ream a hole of greaterdiameter than the drill, as the drill descends. These reamers are shownmost clearly in Figures 7, 8, and 9, and comprise vertically disposed',cutters, the lower portions of 4which are tapered, as shown, and theirupper ends terminatein stems 20, which are pivotally mounted in bearingblocks 21,v which are inserted between the outer pipe section 1 and theadjoining section, and are secured in place 'by bolts or rivets. Similarreamers 19A may also be mounted in the upper end of the drill head, asshown in Fig. 1. In Fig. 10, is shown a reanicr 22, which is adapted toswing outward under centrifugal action. To accomplish this, the reanieris pivotally mounted on a stem 23, the upper portion ofwhich is securedin a support 24,'

'which has a swinging connection with a block 25, which is secured inthe drill head in the same manner as blocks 21 previously described. InFig. 5 is shown a change in the construction of the head. ln thisarrangement, the upper ends of the drill head sections 1A are contractedinto conical forni, as

at 1B, a hole being left inthe apex of each sec t1on of a. diameter`corresponding'to that of the drill stem, and thesectionsare welded to-the stern at these points; 'llie stem in this arrangement is providedwith holes 5^which register with the spaces between 'the conicalportions 1B of the pipe sect-ions, so that Water supplied to the drillstem'will pass to the spaces between the head section and thence to thebottom of the hole. In this view, the coreforming cut-ters 8Aaredispensed withand cutters or reamers 26, similar to the reamers 19,are employed and are mounted in blocks 27, similar in all respects' tothe blocks 2l, vbefore described. All ofthe cutters 8y in the severalviews are held against sliding-movement on the shafts, by washers 9^,whichI are placed upon the shafts between the cutters and the pipesections. l

In Figure 4 is shown a modification in which cutters' 8B are mounted onan inclined shaft 28, which is secured in the cutter head in the samemanner as described in connection with the shafts 9. |The cutters 8B.are'narrower than the cutters 8 and one of these cutters is positionedbetween each two pipe sections.- Tapered or wedge-shaped spacing strips29 are welded to the inner faces of the pipe sections, and the inner.faces of these strips lie parallel with theadja'cent faces of thecutters, and washers 30.are placed upon' the` shaft 281on opposite sidesof the cutters. As these cutters stand at an inclination, their corneredges will'lirst engage the surface to be cut away and thus facilitatethe cutting action.

In Fig. Gis shown a drill adapted for ordinary well drilling, and inthis arrangement, the same character ofcutters are used, as are shown inFigures A2 fand .3, and they are mounted on shafts 9 and 9A, which aresecured in the drill head in the-manner previously described; the onlyrdifference being that .the

' 5, which constructions have been previously shaft 9^ extendsentirelyacross the drill head and upon itscenterportion are mounted twolcutters @which cut away the center portion of the bottom of the holeorwell, the other cutters 8 removing the remaining surface. In otherrespects, the construction of this drill may be as that shown either inFig. 2 or Fig.

described.

`The improved drill may be operated in the usual manner, but preferablyby steam ori` compressed air operated turbines 31, which are mountedupon the drill stem 2 of the drill head. As the turbine forms no partofthe present invention, a detailed description'of the same is deemedunnecessary. The turbines or motors are encased in jackets 32, havingfins 33, which engage the wall of the hole as the drill descends andthus prevent the body of the turbine from turning, while the rotor ofthe turbine, which is secured to the shaft 2, may rotate freely. supplypipe 34 extends from the upper motor to a steam or air sup\ ply, and theexhaust from the upper motor Y a flange 36, and the hanged end 37 of ashort section of pipe 38, is connected to the flanged end of the stem',by a coupler 3 9, which is made of two half round sections which arebolted togetlfer, the sections having enlarged re'.

cesses .to receive'the flanges 3 6 and 37, thus coupling the pipesection ,38 andthe drill stem together, but so as to permit freerotation of the stem 2. A flexible hose-not shown-is attached to thepipe section 38 and extends up through the well to a water supply: .Aguide 40 surrounds the upper end of the drill stein, and is in the formof a hollow cylinder having holes in its opposite ends through which thestem passes, and yholes through which the supply pipe 34 passes, and theguide is formed with fins-41 which engage thef wallv of the well and`prevent the guide from turning. The upper end of rthel guide abutsagainst the lower end 'of the coupler 39. A hollow bell-shaped member'42 is bolted to the top of the guide 4() and its upper ,end tightlysurrounds the pipe section 38, and this end of the member is providedwith apertured @ars 43 to which a lifting cable may be secured. I v

If the drill is operated in the usual inanner, the drill stem-isextended by the addi. tion of coupled sections as the holeprogresses indepth, but if operated as illustrated in Fig. 1, the drill stem extendsonly a relatively short distance' above the upper end 'of the drillhead, to 'receive the motors, and a hose is connected to the stem, asabove set forth.

In operation, if 'a core drill is used, the

same is lowered into a previously drilled hole, and set in motion, andat the same time, water is supplied through the drill stem, and, 1f

`the style of drill shown inFig. 2 is used', the

water passes through theholes`5 in the stem, tothe distributing pipes 6,and through the nipples 7eto the spaces between the drill head pipesections. If the formof dri-ll shown in -ioo Fig. 5, is used, the waterpasses through-y holes .5A immediately to the spaces between the pipesections, and in either case, the water flows directly do'wn uponthe-cutters. When a full length core lis formed,y the head is withdrawndand the core removed therefrom, and the operation is repeated as often'as may be required. When the drill shown in Fig. 6 is used, it iswithdrawn only in case of accrdent or fof replacing worn cutters withnewef ones. Thefreamers -19and I19.A will assure* ample .clearanceLforthe drill head, both while in operation and when the samev 1sHwithdrawn from the--well. As the' cutters are arranged in groupsy andthe cutters'of each group faremounted on a single shaft, which can beeasily removed, the matter of remov- CII ing worn cutters and replacingthem with new ones, can be easily and quickly accomplished.

Having described our invention, whatwe claim as new and desire to secureby Letters Patent, is

l. ln a drill of the characterv described, a hollow drill stem, a headmounted thereon,

comprising a plurality ofspaced, connected tubular sections, arrangedone within another, a block in said stem at a point corresponding withthe top of the head, the stem vhaving outlet holes above said block,which head, said latter cutters having vertical axes.I

2. lai a drill of the character described, a

' hollow drill stem, a head mounted thereon,

comprising a plurality' of spaced, connected,

tubular sections arranged one within another, a block in said steml on aplane with the top of the head, the stem having outlet holes abovesaid'block, which communicate with the spaces between said tubularsections, the portion of thestem below the block constituting a lcorebarrel, opposite blocks in the lower end of the head, adjacent the corebarrel and gravity cuttingdogs pivotally mounted in said blocks andadapted to swing out into the core barrel through slots in said barrel,radially disposed shafts in the lower end of the head,4havingA rotarycutters thereon, those on one shaft travelling in a different path fromthose on the adjoining shafts, two diametrically opposite cutters beingcoreforming cutters, said gravity dogs being in inoperative positionsduring the core forming operation.

3. The combination with a hollow l drill stem, of a head thereon,comprising spaced tubular sections arranged one within another andsecured upon saidstem, said sections having recesses in their. loweredges in radial alinement, shafts having'squared portions which entersaid` recesses and saddle blocks which are secured in the ends of saidsections to hold said shafts in place, said shafts having Arotarycutters thereon, a block in said stem on a plare with the top of thehead, y

said stem having. holes above said block which communicate with thespaces between said sections, and cutters in the periphery of said headwhich travel in a path of greater diameter than that of the head.

In testimony whereof, we aHX our signatures.

ANDREW B'. oRoSs. l wiLLiAM H. FRAZIER.

